Institutions are relying increasingly on their data communication network infrastructures for efficient communication and data transfer. With this increasing reliance on network computing has arisen a significant need for mechanisms to regulate connectivity to and communicability within such networks. This need has been partially filled by internet protocol (IP) firewalls. IP firewalls typically restrict access to fixed sets of network resources by applying a set of protocol level filters on a packet-by-packet basis or by requiring prospective users to become authenticated before gaining access to the resources. Authentication has generally required users to supply certain signature information, such as a password. While this requirement of signature information has reduced the risk of unauthorized access to firewall-protected resources, firewalls have proven an imperfect and inflexible regulatory solution. Because firewalls are protocol-specific, firewalls have not provided a means for regulating network connectivity in a multi-protocol environment. Moreover, because firewalls regulate access to particular network resources, they have failed to provide a means for regulating access to sets of network resources which can vary as a function of user identity.
Protocol-independent mechanisms have also been deployed for authenticating users of the resources of institutional networks. However, such authentication mechanisms are only known to have been deployed to challenge remote users attempting to log-in over dial-up phone lines. Such mechanisms are not known to regulate the network access of local users logging-in over a LAN interfaces, such as Ethernet or Token Ring interfaces. Moreover, such mechanisms have, like firewalls, provided an inflexible solution which is unable to regulate access to customized or personalized sets of resources within the network based on user identity.
The flexibility limitations of the foregoing log-in challenge mechanisms have been partially overcome by independently implementing virtual local area networks (VLANs) within institutional networks. VLANs are sub-networks which typically include a plurality of network devices, such as servers, workstations and PCs, that together form a logical work group within a larger network. Because VLAN membership is assigned based on policies rather than physical location in the network, network bandwidth has been conserved and network security enhanced by assigning VLAN membership based on considerations of efficiency and need and restricting the flow of network traffic across VLAN boundaries.
While significant security and efficiency gains have been realized by policy-based VLANs, the solution they have offered is far from complete. VLAN membership has generally been assigned to end systems without reference to the identity of the users of such systems. In the current technology, for instance, VLAN membership is typically assigned by comparing network traffic with a configured set of rules which classify the traffic, and by inference the system which originated the traffic, into one or more VLANs. The identity of the user who sent the traffic is not considered in the assignment process. The failure to consider user identity leaves some network security issues unaddressed. Particularly, a person not authorized to use the resources of a VLAN may be able to gain access to its resources by transmitting data packets which the configured rules will classify into the VLAN, either by communicating over a member end system or by spoofing the required identifiers. Known VLAN assignment methods have also failed to contemplate providing conditional access to users based on the day of the week, the time of day, the length of access or a combination of such factors. Furthermore, current networking equipment and policy-based VLANs in particular have not offered collateral functionality, such as the ability to dynamically track where local users are connected to the network. Such a tracking mechanism would greatly simplify tasks such as network troubleshooting by allowing the network location of a user requesting technical support to be easily determined.
Accordingly, there is a need for comprehensive services for regulating communicability in institutional networks which are not subject to the inflexibility of conventional user log-in mechanisms or the lack of consideration for user identity of conventional VLAN assignment techniques. There is also a need for services which authenticate local users of institutional networks before establishing network communicability. There is a further need for user authentication services which provide collateral functionality, such as the ability to dynamically track the whereabouts of network users.